Borates and Pets

[ashtonfitzgerald]

Okay so I've read now a few times from a few sources stating that borates in pool water are dangerous for pets. I have yet to come across a scientific article that confirms this.

Many studies look at the toxicity of various borate salts and there has been clear evidence of the ability of boric acid and sodium tetraborate to affect fertility and fetal development.

I have further heard (with no substantiation) of claims that borax is dangerous to children and animals if ingested. Obviously if there is some canine-specific mechanism of sensitivity that is possible, however if borax is in fact dangerous at what concentration is it of concern.

This summary seems to indicate that there is no discernible difference across species: Comparative toxicology of borates | SpringerLink

Like so many things I have no issue either way, but hope to know the truth.

Thanks!


QUICK EDIT:

I ran some numbers and worked out the 30ppm borate target for our pools is essentially 265mg/L sodium tetraborate. For a 25kg body (medium dog or child) consuming 1 L of pool water this is 10.6mg B/kg and is above the lowest observed animal NOAEL of 9.6mg B/kg. This calls into question if borates are "safe" for children who may at anytime accidentally or on purpose consume pool water. I do recall reading that boric compounds are easily passed through the body system and excreted through urine.

 

[tim5055]

Generally topics like this end ou in our "Deep End" forum and can be discussed for a long time.

The best any of us have been able to surmise is that the limit for borates in a pool for dogs (I think that is the only species testing has been done on) of no adverse effects is 50ppm. Just the idea that dogs have a lower adverse effect threshold than humans made it easy for me to decide no borates in my pool.

This is a quote from THIS THREAD Are Borates Safe to Use?

A 100 pound dog would need to drink 8 liters (over 8 quarts) of 50 ppm borate pool water every day just to be at the No Observed Adverse Effect Limit (NOAEL). The level seen for first symptoms is 3 times higher than this amount. And this is literally drinking every day since borates are excreted from the body and do not accumulate so the daily intake level where problems would occur is that which is higher than the rate at which the body flushes out borates. Boron is an essential nutrient so the body takes in what it needs and excretes the rest, though this process has its limits which is why almost anything is toxic if given in high enough doses. This excretion process is fairly efficient for mammals that use urine primarily to excrete excess nitrogen as urea, but for insects they excrete solid uric acid so do not excrete boron efficiently which is why boron is far more toxic to them.

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[ashtonfitzgerald]

Now I feel like I fool....I just found the post by Chemgeek that was linked in the sticky above....

 

[tim5055]

I ran some numbers and worked out the 30ppm borate target for our pools is essentially 265mg/L sodium tetraborate. For a 25kg body (medium dog or child) consuming 1 L of pool water this is 10.6mg B/kg and is above the lowest observed animal NOAEL of 9.6mg B/kg. This calls into question if borates are "safe" for children who may at anytime accidentally or on purpose consume pool water. I do recall reading that boric compounds are easily passed through the body system and excreted through urine.

Your numbers seem to conflict with Richard's (Chem Geek). He is very precise with his numbers.

 

[ashtonfitzgerald]

Yup, I was basing my numbers on the actual weight of borax required to hit the target as opposed to the actual weight of the "active ingredient" so to speak.

I'm glad to have found the post from Richard as I trust the leg work he has put into things, and being much more knowledgeable in these areas than myself I'm certain he has covered a lot of bases.

In general terms, this has answered my question that it's not a canine-specific physiological mechanism that makes borates a concern. Just don't let the dog drink the pool water, really no different than the rules we have for kids. Have I mentioned I enjoy diving into the deep end (even if I can't swim all that well [emoji6]).

 

[bmoreswim]

It is impossible for our dogs to not drink the pool water, even though I never see them leaning over and drinking it. They ingest it when they are swimming with balls in their mouths. I know they ingest it then because of the extra amount they pee for the next couple hours after swimming. They only go in the water to fetch balls - because we don't let them swim with us!

I saw no real reason to use borates that couldn't be solved in another manner. And having a northern pool in a rainy locale, we drain in winter and dilute in summer due to dog splashout/rain cycle, so I would perpetually be adding to maintain the borate level. Another expense I don't need. And borates only delay the need for MA, they don't change the amount you need over time.

 

[ashtonfitzgerald]

I agree it would absolutely be another point of concern especially with the wording yet drain, spring refill cycle. We have the same issue being in southern Ontario. I haven't crossed the borate bridge, but do use borax from time to time. For me it's more about knowing about potential for danger for the kids firstly, pets second (my dogs only go in the pool a handful of times each season).